Torque Converter Lockup Clutch With Axial Wedge Constraint
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing torque converters with lockup clutches face challenges in maintaining controlled engagement and disengagement due to axial displacement issues, leading to inconsistent performance and delayed engagement as friction materials wear out.
Innovation Solution
A lockup clutch design incorporating a piston with a first wedge surface and a support, along with a wedge featuring a second wedge surface, where the angled surfaces prevent axial displacement, ensuring consistent engagement and disengagement by limiting piston movement, thus improving controllability and maintaining tight clearance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a traditional lockup clutch design is used without axial constraint mechanism, then the structure is simpler, but the piston experiences uncontrolled axial displacement leading to inconsistent engagement and delayed performance
Solution Approach 1:
The clutch assembly is segmented into distinct functional components: the piston with first wedge surface, the wedge with second wedge surface, and the support structure. This segmentation allows the axial constraint function to be implemented as a separate module without redesigning the entire clutch system, thereby improving reliability while minimizing added complexity.
Solution Approach 2:
The wedge acts as an intermediary element between the piston and the support. It translates axial movement of the piston into radial force through the wedge surfaces, providing controlled axial constraint. This intermediary mechanism ensures consistent engagement without requiring direct complex constraints between the piston and support.
2Duration of action of stationary object
If friction materials are allowed to wear naturally, then the clutch operation is simpler, but engagement timing becomes delayed and performance degrades
Solution Approach 1:
The wedge surfaces are pre-configured with specific angles and positions to maintain optimal engagement geometry throughout the clutch's operational life. This preliminary geometric arrangement compensates for friction material wear by ensuring that the axial constraint force remains consistent even as the friction materials degrade, thereby extending performance duration without engagement delay.
3Ease of operation
If the piston is allowed free axial movement, then the clutch structure is simpler, but the liftoff distance becomes inconsistent reducing controllability
Solution Approach 1:
The wedge surfaces are designed with curved geometries that guide the piston's axial movement smoothly. The curved surfaces ensure consistent liftoff distance by maintaining uniform contact pressure distribution, improving controllability while keeping the constraint mechanism relatively simple through geometric design rather than complex mechanical stops or springs.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution enhances the controllability of the lockup clutch by maintaining consistent liftoff distance and preventing excessive axial displacement, ensuring reliable torque transfer and prolonged clutch performance even as friction materials wear.
Implementation Method 1
a first wedge surface... a wedge including a second wedge surface... contact between the first wedge surface and the second wedge surface limits axial movement
Data Source
AI summary
A lockup clutch for a torque converter is provided. The lockup clutch includes a piston including a first wedge surface and a support supporting the piston. The piston is axially slidable along the support in a first axial direction to cause engagement of the lockup clutch. The lockup clutch also includes a wedge including a second wedge surface. The wedge is axially movable along the support. The first wedge surface is arranged and configured with respect to the second wedge surface such that contact between the first wedge surface and the second wedge surface limits axial movement of the piston in a second axial direction opposite the first axial direction. A torque converter and a method of forming a lockup clutch are also provided.